2-chloroethane-phosphonic-(or thiono phosphonic) acid amido compounds as plant growth regulants

ABSTRACT

2-CHLOROETHANE-(THIONO)-PHOSPHONIC ACID AMIDO COMPOUNDS OF THE FORMULA   in which X is oxygen or sulfur; R is lower alkyl radical of from 1 to 6 carbon atoms or phenyl; and R&#39;&#39; is hydrogen atom or a phenyl radical which may be substituted by nitro, halogen, alkyl or hydroxy; or R&#39;&#39; can represent an agriculturally acceptable salt moiety, e.g., R&#39;&#39; can be an alkali metal or equivalent, an alkaline earth metal or equivalent, an ammonium radical or equivalent, ARE OUTSTANDINGLY EFFECTIVE AS PLANT GROWTH REGULANTS TO STIMULATE, INHIBIT OR ALTER THE GROWTH OF PLANTS OR PARTS THEREOF.

United States Patent [191 Hofer et a1.

[451 Aug. 26, 1975 [73] Assignee: Bayer Aktiengesellschaft,

Leverkusen, Germany [22] Filed: Sept. 29, 1970 [21] Appl. No: 76,595

[30] Foreign Application Priority Data Oct. 4, 1969 Germany 1950100 [52] US. Cl. 71/76; 71/71; 71/76; 71/77; 71/78; 71/86; 71/87 [51] Int. Cl. A0ln [58] Field of Search 71/86, 87, 77, 76, 78, 71/69, 71

[56] References Cited UNITED STATES PATENTS 3,531,549 9/1970 Randall M 71/86 X 3,551,528 12/1970 Randall 1 1 1 71/86 X 3,600,435 8/1971 Randall et a1 I 71/86 X 3,679,780 7/1972 Randall et a1 1 71/86 3,733,192 5/1973 Harris et a1. 71/86 FOREIGN PATENTS ()R APPLICATIONS 803,947 1/1969 Canada .1 71/86 Primary ExaminerJames 0. Thomas, Jr. Attorney, Agent, or Firm-Burgess, Dinklage & Sprung [57] ABSTRACT 2-chloroethane-(thiono)-phosphonic acid amido compounds of the formula X NH R in which X is oxygen or sulfur; R is lower alkyl radical of from 1 to 6 carbon atoms or phenyl; and R is hydrogen atom or a phenyl radical which may be substituted by nitro, halogen, alkyl or hydroxy; or R can represent an agriculturally acceptable salt moiety, e.g., R' can be an alkali metal or equivalent, an alkaline earth metal or equivalent, an ammonium radical or equivalent, are outstandingly effective as plant growth regulants to stimulate, inhibit or alter the growth of plants or parts thereof.

17 Claims, No Drawings 2-CHLOROETHANE-PHOSPHONlC-(OR THIO'NO PHOSPHONIC) ACID AMIDO COMPOUNDS AS PLANT GROWTH REGULANTS The present invention relates to the use of certain I.- chloroethanc-(thiono)-phosphonic acid amido compounds as agents for the regulation of plant growth.

It is known from Dutch Pat. Specification No. 6.802.633] that Z-chloroethanephosplionic acid exhib its plant-growth-regulating properties.

The present invention provides a method for the control of plant growth which comprises applying to the plant or seed thereof a 2-chloroethane-phosphonic acid amido or 2-chloroethanc-thionophosphonic acid amido compound of the general formula in which X is oxygen or sulfur;

R is lower alkyl radical of from 1 to 6 carbon atoms or phenyl; and

R is hydrogen atom or a phenyl radical which may be substituted by nitro. halogen. alkyl or hydroxy; or R' can represent an agriculturally acceptable salt moiety. e.g. R can be an alkali metal or equivalent. an alkaline earth metal or equivalent. an am monium radical or equivalent. either alone or in admixture with a solid or liquid diluem or carrier.

Some of the above compounds are known to have fungicidal effects. It was. however. very surprising that the compounds used in this invention have plantgrowth-regulating properties. Unexpectedly. the 2- chloroethane(thino)-phosphonic acid amido com pounds according to the invention show a considerably higher plant-growth-regulating activity than the 2- chloroethanephosphonic acid known from the prior art. This acid is chemically the closest active compound of the same type of activity. The substances according to the invention therefore represent a valuable enrichment of the art.

The substances to be used according to the invention are defined by the general formula (I). wherein R is preferably lower alkyl radicals of from I to 4 carbon atoms or for a phenyl radical; and R is preferably hydrogen or phenyl. which may be substituted with ni' tro. methyl. hydroxy or chlorine.

As examples of the active compounds which can be propylamide. Z -chloroethanc-phosphonic propylamide.

acid-mono-Niso- Z-chlorocthane-phosphonic acid mono-N-nbutylamide. 2chloroethane phosphonic acid mono-N-scc.-

butylamidc.

lll

2 Z-chloroethane-phosphonic acid mono N-tel'ti hutylamidc. 1chlorocthane-phosphonic acid inono-N-iso hutylamidc.

Z-chloroethane-phsophonic acid mono-N- phenylamide. Z-chloroethanc-thiono-phosphonic acid mono,\l-

methylamide. 2-chloroethane-thiono-phosphonic acid mono-l\i ethylamide. 2-chloroethane thiono-phosplionic acid mono-N-n-propylamide. Z-chlorocthanc-thiono phosphonic acid monoN-isopropylamidc. 2-chlorocthane-thiono-phosphonic acid mono-Nam butylamidc.

2-chloroethanethiono-phosphonic acid mono-N- sec.-butylamidc. Z-chlorocthanc-thiono-phosphonic acid mono-N- tert.butylamidc.

Z-chlorocthane-thiono-phosphonic acid niono-N-isobutylamide.

Z-chloroethane-thiono-phosphonic phenyl-amide. in addition. the sodium. potassium. ammonium. calcium and barium salts of these (thiono)-phosphonic acid amides. further. their:

2'-h ,'droxyphenyl esters. 3-hydri.ixyphenyl esters.

4'-hydroxyphenyl esters. 2-nitrophenyl esters.

3-nitrophenyl esters. 4' nitrophenyl esters.

2'-cresyl esters. 3'-cresyl esters. 4'-cresyl esters.

2-chlorophenyl esters. 3'-chlorophenyl esters.

4'-chlorophenyl esters. Z'.4'-dichlorophcnyl esters and 2'.b'-dichlorophenyl esters.

Some of the substances which can be used according to the invention are known. e.g. Z-chloroethane thiono phosphonic acid 2'.-'1'-diehlorophenyl ester mono-Nisopropylamide [see Russian Patent Specification [97.359 and Z. Obsc. Chim. (Journal of General Chemistry of the U.S.S.R.) 38 (1968). No. l0. pp. 2260 2265 Some of the substances used in the invention are new. but they can be prepared in simple manner ac cording to known processes. They are obtained for example when Z-chloroethane-(thiono)-phosphonic acid amide chlorides are reacted with phenols in the pres ence of inert solvents. such as benzene. and acidbinding agents. for example triethylamine. at temperatures of 0 to C. The reaction products may be isolated by filtering off the precipitated solids with suction. washing the organic phase with water. subsequcntly drying it over sodium sulphate and. finally. drawing off the solvent in a vacuum.

As examples of the 2-chloroethane-(thiono)- phosphonic acid amide chlorides which can be used for preparing compounds to be used in the invention. there are mentioned in particular:

acid mono-N 2-chloroethane-phosphonic acid N-methylamide chloride.

Z-ChIoroethane-phosphonic acid N-iso-propylamide chloride,

2-chloroethane-phosphonic acid anilidc chloride.

2-chloroethane-thionophosphonic acid N- methylamidc chloride.

2chloroethanc-thiono-phosphonic acid N-isopropylamide chloride. The 2-chloroethane-(thiono)-phosphonic acid amide chlorides used as starting materials are not all known 3 but can readily be prepared by reacting 2- chloroethane-tthiono)-phosphonic acid dichloride with primary amines in the presence of an inert solvent. such as eg. benzene. and an acid-binding agent. for example excess amine. at temperatures from l to 50C. Working up may take place according to customary methods. Examples l to 24. below. illustrate the preparation of active compounds and their precursors.

The active compounds which can be used according to the invention interfere with the physiological phenomena of plant growth and can therefore be used as plant growth regulators.

The different effects of the active compounds depend essentially on the point in time of the application. with reference to the development stage of the seed or the plant. as well as on the concentrations applied.

Plant growth regulators are used for various purposes which are connected with the development stage of the plant. Thus. with plant growth regulators the seed dormancy can be broken in order to cause the seeds to germinate at a certain desired time at which the seed itself shows no readiness to germinate The seed germination itself can by such active compounds. depending on the concentration applied. either be inhibited or promoted. This inhibition or promotion relates to the seedling development. The bud dormancy of the plants. that is to say the endogenic annual cycle. can be influenced by the active compounds so that. for example. the plants shoot or blossom at a point in time at which they normally show no readiness to shoot or blossom. The shoot or root growth can be promoted or inhibited by the active compounds in manner dependent on concentration. Thus. it is possible to inhibit very strongly the growth of the fully formed plant. or to bring the plant as a whole to a more robust habitus or to produce a dwarf growth.

Possible economic applications include the suppression of grass growth at roadsides and waysides. and the inhibition of the growth of lawns so that the frequency of grasscutting (of lawn-mowing) can be reduced.

During the growth of the plant. the branching to the side can also be multiplied by a chemical breaking of the apical dominance. This is particularly useful in the case of propagation of plants by cuttings. ln concentra tiondependent manner. however. it is also possible to inhibit the growth of side-shoots. for example in order to prevent the formation of side-shoots in tobacco plants after decapitation and thus to promote the leaf growth.

In the case of the influencing of blossom formation. there can be achieved. in manner dependent on concentration and the point in time of the application. either a retarding or an acceleration of blossom formation. ln certain circumstances. a multiplication of blossom initiation can also be obtained. these effects occurring when the appropriate treatments are carried out at the time of the normal blossom formation.

The influence of the active compounds on the foliage of the plants can be so regulated that defoliation is achieved. for example in order to facilitate the harvest or to reduce transpiration at a time at which the plants are to be transplanted.

Fruit initiation can be promoted so that more fruits or seedless fruits are formed (parthenocarpy). ln certain conditions. the premature fall of fruit can also be prevented. or the fruit fall can be promoted up to a certain extent in the sense of a chemical thinning out. The

4 property of promoting the fruit fall can also be ex ploited by effecting the treatment at the time of the harvest. whereby harvesting may be facilitated.

By spraying the unripe fruits with the compounds according to the invention. the ripening process can also be accelerated and a better colouring of the fruits can be achieved.

The active compounds to be used according to the present invention can be converted into the usual formulations. such as solutions. emulsions. suspensions. powders. pastes and granulates. These may be produced in known manner. for example by mixing the ac tive compounds with extenders. that is. liquid or solid diluents or carriers. optionally with the use of surfaceactive agents. that is. emulsifying agents and/or dispersing agents. in the case of the use of water as an exten der. organic solvents can. for example. also be used as auxiliary solvents.

As liquid diluents or carriers. there are preferably used aromatic hydrocarbons. such as xylenes or benze ne. chlorinated aromatic hydrocarbons. such as chlorobenzenes. paraffins. such as mineral oil fractions. alcohols. such as methanol or butanol. or strongly polar solvents. such as dimethyl formamide or dimethyl sulphoxide. as well as water.

As solid diluents or carriers. there are preferably used ground natural minerals. such as kaolines. clays. talc or chalk. or ground synthetic minerals. such as highly-dispersed silicic acid or silicates.

Preferred examples of emulsifying agents include non-ionic and anionic emulsifiers. such as polyoxyethy lene-fatty acid esters. polyoxyethylcne-fatty alcohol ethers. for example alkylarylpolyglycol ethers. alkyl sulphonates and aryl sulphonates'. and preferred examples of dispersing agents include lignin. sulphite waste liquors and methyl cellulose.

The formulations contain. in general. from 0.l to 95. preferably 0.5 to 90. per cent by weight of active compound.

The active compounds may be applied as such or in the form of their formulations or of the application forms prepared therefrom. such as ready-to use solutions. emulsifiable concentrates. emulsions. suspensions. spray powders. pastes. soluble powders. dusting agents and granulates. Application may take place in customary manner. for example by watering. squirting. spraying. scattering. dusting. etc.

The concentrations of active compound can be varied within a fairly wide range for actual application. In general. concentrations of 0.0005 to 2% by weight. preferably 0.0l to 0.5%. are used.

Further. there are applied. in general. 0.l to kg. preferably l to If) kg. of active compound per hectare.

The growth regulators are desirably applied on a preferred time period. the precise delimitation ofwhich is governed by the climatic and vegetative circumstances. as known to those skilled in the art.

The substances according to the invention possess also activity against plant-damaging bacteria.

In the following tests. carried out to demonstrate the bio-activity of the instant compounds. the following were chosen as representative test compounds:

acid phcnyl COMPOUND 2 acid-2-hydroxy-phenyl COMPOUND 3 2-chloroethane-phosphonic acid-mono-N-isopropyl amide COMPOUND 4 EXAMPLE A Growth inhibition/linseed test Solvent: 40 parts by weight acetone Emulsifier: 0.25 part by weight alkylaryl polyglycol ether To produce a suitable preparation of active compound 1 part by weight of active compound was mixed with the stated amount of solvent which contained the stated amount of emulsifier. and the concentrate was diluted with a disodium hydrogen phosphate-potassium dihydrogen phosphate buffer solution (pH 6) to the desired concentration Two batches of 25 linseeds were each laid out on a filter paper in a Petri dish. 10 ml of the preparation of active compound were pipetted into each dish. Germination of the seeds took place in the dark at 25C.

After 3 days the length of the shoot and the roots was determined and the growth inhibition compared with the control plant is expressed as a percentage. lO07 denotes the standstill of growth and 0% denotes a growth corresponding to that of the untreated plant.

The active compounds. the concentrations of the active compounds in ppm mg/kg) and results can be seen from Table A.

Table A Active compound Growth inhibition/linseed 75 inhibition with 250 ppm n HO Table A-continued Growth inhibition/linseed Active compound '4 inhibition with 250 ppm root shoot Compound 3 2-chloroethane-phosphonic acid-mono-N-isopropyl amide NHC H -i ll Cl-CH- -(H. ,P 42 53 OH I EXAMPLE 8 EXAMPLE C Growth inhibition and defoliation/beans Solvent: 40 parts by weight acetone Emulsifier: 0.25 part by weight alkylaryl polyglycol ether Table B Growth inhibition/wheat Solvent: parts by weight acetone Emulsifier: 0.25 part by weight alkylaryl polyglycol ether To produce a suitable preparation of active compound, 1 part by weight of active compound was mixed with the stated amount of solvent which contained the stated amount of emulsifier, and the concentrate was diluted with a disodium hydrogen phosphate-potassium dihydrogen phosphate buffer solution (pH 6) to the desired concentration.

Wheat plants of a size of 4 cm were sprayed with a preparation which contains 5000 ppm of active compound. After 10 days, the average length of the wheat was evaluated.

The active compounds and results can be seen from Table C.

Growth inhibition and defoliation/beans Active compound Length in cm Number ofleavcs water [7,0 1 control I (known) Compound 1 2-chlorocthanephosphonic acid phenyl ester-N'mono-isopropyl amide Compound 3 2-chlorocthanc-phosphonic acid-mono-N-isopropy| amide Compound 4 243hloroethanc-thiono-phosphonic acid phenyl ester-Nmiono-methyl amide Table C G rowth in hihitinn/wheat Table D Growth inhibition/beans tuatcring tcsl) Active compound Length in cm Active cumpnund Length in cm water 200 water 25.0 (control) (control) 0 ()H 0 OH H/ H/ Ci-LH. CH -P\ as Cl CH CH P\ [4.

OH OH (kno n! [known] Compound 4 Zchloruethane-thinno- Compound l 2-chloroethane-phosphonic acid phosphonic acid phcnyl cstcr-N monophenyl cster-N-mono'isnpropyl amide methyl amide o NH-C;,H,i s NHCH;, ll/

C| CH, CH P 1 .0 ci cH cH P 6.0

Compound 3 2 chloroethanc-phusphonic acid mono-N-isopmpyl amide 0 NHC;.H,-i EXAMPLE D CICH,CH2P\ 1L5 Growth inhibition/beans (watering test) 0H Solvent: 40 parts by weight acetone Emulsifier: 0.25 part by weight alkylaryl polyglycol ether EXAMPLE E To produce a suitable preparation of active com- Growth mh'blt'on/mmet pound, 1 part by weight of active compound was mixed Solvent: 40 parts by weight acetone with the stated amount of solvent which contained the Emulsifier: 0.25 part by weight alkylaryl polyglycol stated amount of emulsifier and the concentrate was ether diluted with a disodium hydrogen phosphate-potassium dihydrogen phosphate buffer solution (pH 6) to the de- To produce a suitable preparation of active comsired concentration. pound, 1 part by weight of active compound was mixed Three bean plants (of a height of 10 cm) in a pot (9 with the stated amount of solvent which contained the cm diameter) were watered once with a preparation of stated amount of emulsifier. and the concentrate was active compound corresponding to an applied amount diluted with a disodium hydrogen phosphate-potassium of IO kg/hectare. After 8 days, the length of the beans dihydrogen phosphate buffer solution (pH 6) to the dewas determined. sired concentration.

The active compounds and results can be seen from Millet plants (Panicum miliaceum) of a size of 4 cm Table D. were sprayed with a preparation which contained 2000 and I000 ppm of active compound. After 6 days. the growth increase was evaluated.

The active compounds and results can be seen from Table E.

Table E-continued Growth inhibition/millet Active compound Concentration Growth increase in ppm in cm Compound 2 LChIoroethanc-phosphonic acid2-hydroxy-phenyl ester-N-mono-isopropyl amide O NHC;;H-,i

ll C|-CH:-CH P\ ZlltlO 1.0 O lllllil 4.0 Hon EXAMPLE F Acceleration of fruit ripeness/tomato plants Solvent: 40 parts by weight acetone Emulsifier: 0.25 part by weight alkylaryl polyglycol ether To produce a suitable preparation of active compound, 1 part by weight of active compound was mixed with the stated amount of solvent which contained the stated amount of emulsifier and the concentrate was diluted with a disodium hydrogen phosphate potassium dihydrogen phosphate buffer solution (pH 6) to the desired concentration.

Green, unripe fruits of tomato plants were sprayed once with a preparation which contained 5000 ppm of active compound. An accelerated ripening of the fruits was thereby achieved.

The active compounds and results can be seen from Table F.

Table F Acceleration of fruit ripeness/Tomato plants Active compound Acceleration of ripeness in days water (control) OOH lknownl Compound 3 2-chlorocthane phosphonic acid-mono Nisopropyl amide Table F continued Acceleration of fruit ripeness/Tomato plants Active compound Acceleration of ripeness in days EXAMPLE G Growth inhibition/Linseed Solvent: 40 parts by weight acetone Emulsifier: 025 parts by weight alkylaryl polyglycol ether To produce a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent which contains the stated amount of emulsifier. and the concentrate is diluted with a disodium hydrogen phosphatepotassium dihydrogen phosphate buffer solution (pH 6) to the desired concentration.

Two batches each of 25 linseed are each laid out on a filter paper in a Petri dish. l0 ml of the preparation of active compound are pipetted into each dish. Germination of the seeds takes place in the dark at 25C.

After 3 days, the length of the shoot and the roots is determined and the growth inhibition compared with the control plant is expressed as a percentage. 100% denotes the standstill of growth. and 0% denotes a growth corresponding to that of the untreated plant.

The active compounds. the concentrations of the active compounds in pmm (mg/kg) and results can be seen from the following Table Table G Active compound Table (i-continued (iroiath inhibition/linseed Aeliie compound inhibition of the shoot ith 50 ppm 250 ppm S NH('H ;H i

('l-CH:( 'H -P\ 33 60 S NH(',H. n H CICH -CH P\ 50 64 O NHC.H,.n ll/ CI-L'H.. LH P\ so so The preparation of the compounds to be used ae- EXAMPLE 7 cording to the invention. and of precursors therefore (Examples 1 and 2), is illustrated by the following Ex amples 1 to 24.

EXAMPLE 1 Preparation of 2-chloroethanethionophosphonic acid phenyl ester mono-N-methylamide mains behind. The yield is 35 g (70%) of 2- ehloroethanethionophosphonie acid phenyl ester mono-N-methylamide.

Analysis: S N C1 cine. l'or C,,H,CINOPS: sti /i 5.!'4. 14.20%; Found: a 1m .62%. 14.26%.

The 2-chloroethanethionophosphonic acid mono-N- methylamide chloride required as starting product is prepared as follows:

15.5 g (0.5 mole) methylamine in 200 ml toluene are added to 49.5 g (0.25 mole) 2- chloroethanethionophosphonic acid dichloride in 500 ml toluene. Stirring is effected for one hour. the salts are then filtered off with suction; washing with water is effected. followed by drying over sodium sulphate. and the solvent is drawn off. After "slight distillation" at 0.1 mm Hg/80C. a yellow oil remains behind. Yield: 41 g (85 i of the theory I; m, 1.5613.

Preparation of 2ehloroethanephosphonic acid mono-Nisopropylamide 12 g (0.3 mole) NaOH in 20 ml water are added dropwise at 40C. with stirring. to 61 g (0.3 mole) 2- chloroethanephosphonic acid mono-N-isopropylamide chloride in 500 ml acetone. Stirring is continued for a further 2 hours at room temperature. suction filtration from precipitated salt is effected and the solvent is subsequently drawn off. There remain behind 53 g (697:) of 2-chloroethanephosphonic acid mono-N- isopropylamide. hygroscopic crystals of mp 102 108C. 4

The 2-chloroethanephosphonie acid mono-N- isopropylamide chloride required as starting product is prepared as follows:

59 g (1 mole) i-propylamine are added at 0C to 91 g (0.5 mole) 2-chloroethanephosphonic acid dichloride in 1.5 1 oftoluene. Stirring is then effected for one hour at room temperature. The salts are filtered off with suction. then washed with a little water. and the solvent is drawn off. After slight distillation at 0.01 mmHg/. a yellowish oil remains behind.

Yield: 93 g (91%) m, 1.4854.

EXAMPLE 3 Preparation of 2-ehloroethanephosphonie acid phenyl ester mono-N-isopropylamide mole) potassium carbonate and 500 ml acetonitrile. Stirring is then effected for 2 hours at 60C. suction fil Analysis: P (l Cale. for C H flNo P' 11.9%. 13.60:

Found. 12.5%; H.039

EXAMPLE 4 Preparation of 2-ehloroethanephosphonic acid 2'-hydroxyphenyl ester monoN-isopropylamide 30 g (0.3 mole) triethylamine are added at room temperature to 500 ml benzene. 61 g (0.3 mole) 2- chlorethanephosphonic acid mono-N-isopropylamide chloride (cf. Example 2) and 33 g (0.3 mole) eatechol. Stirring is then effected for 2 hours at room temperature; suction filtration from precipitated salts is effected. followed by washing with a little water (about 100 ml) and drying over sodium sulphate. The solvent is subsequently drawn off and. finally. slight distillation is effected at 0.01 mmHg and 60C. A pale oil remains behind. Yield 48 g (58%) of 2- chloroethanephosphonie acid 2'-hydroxyphenyl ester mono-N-isopropylamide; m, 1.5344.

Analysis: N Cl Calc. for C H CINO PI 5.03%: 12.24%.

Found: 5.2295; 11.0%

EXAMPLE 5 Preparation of 2-chloroethanethionophosphonic acid 4"chlorophenyl ester N-monoisopropylamide Analysis ('1 N S (tile. for C H CI NOPS 12.70): 4 50'). it) Found: 211.5"9; 4.02'5: 10.271.

The starting product used is prepared as follows:

A solution of 65 g (0.5 mole) 4-ch1orophenol and 20 g (0.5 mole) sodium hydroxide in 200 ml water is added to 99 g (0.5 mole) 2- chloroethanethionophosphonic acid dichloride. Stirring is then effected for one hour at room temperature. followed by taking up in methylene chloride and separation of the aqueous phase. After washing with water and drying with sodium sulphate. the solvent is drawn off and slight distillation is effected. Yield: 86 g (597: of the theory) 2-chloroethanethionophosphonic acid 4'-chlorophenyl ester chloride, n 1.5856.

Analogously with Example 5. the following compounds are prepared:

EXAMPLE 6 Preparation of 2-chloroethanethiono-phosphonic acid 4'-methyl-phenyl ester N-monodsopropylamide O CH.

Yield: 76% of theory. mi": 1.5542. The starting product 2-chloroethane-thiono-phosphonic acid 4'-methyl phenyl ester chloride is obtained analogously with Example 5 in a yield of 6471. n 1.5686.

EXAMPLE 7 Preparation of Z-Chlorocthane-thiono-phosphonic acid 2-chloro-pheny1 ester N-mono-isopropylamide Yield: 66%. n :1.5687. Starting product: 2-

ehloroethane-thiono-phosphonic acid 2'-chlorophenyl ester chloride. Yield: 6671. n,,: 1.5862.

EXAMPLE 8 Preparation of 2-chloroethane-thiono-phosphonie acid 2', 6'-dichlorophenyl ester N-mono-isopropylamide Cl 5 ll, (l L'H- (H 1\ cl 17 Yield. 53%. melting point 101C. Starting product: 2-ch1oroethane-thiono-phosphonic acid 2'.6'-dichloro phcnyl ester chloride. yield: 53%. mi: 15944.

EXAMPLE 9 Preparation of 2-chloroethane-thiono-phosphonic acid 2.-1'-dichloro-pheny1 ester N-mono-isopropylamide Cl e (I Cl (tl. CH. P

NHC;,H;--i

Yield: 735 1. n 1.5790. Starting product: 2-

chloroethane-thiono-phosphonic acid 2',4'-diehlorophenyl ester chloride. yield: 607:. n,,'-": 1.5962.

EXAMPLE 10 Preparation of 2-chloroethane-thiono-phosphonic acid 3'-chloro-phenyl ester N-mono-isopropylamide Yield: 8471. n,,: 1.5668. Starting product: 2

chloroethane-thiono-phosphonic acid 3'-chloro phenyl ester chloride. yield: 73%. n 1.5851.

EXAMPLE 1] Preparation of 2-chloroethane-thiono-phosphonic acid 2',4'-dichloro-phenyl ester N-mono-methylamide Yield: 66%. n 1.5900. Starting product compare Example 9.

EXAMPLE 12 Preparation of 2chloroethane-thiono-phosphonie acid 3'-ch1oro-phenyl ester N-mono-methylamide Yield: 797:. mi": 1.5840. Starting product: compare Example 10.

EXAMPLE [3 Preparation of 2-ehloroethane-thiono-phosphonic acid phenyl ester N-mono-ethylamide 18 Yield: 81'1. n,,-": 1.5626. Starting product: 2- chloroethane-thiono phosphonic acid phenyl ester chloride. yield: 77%. 11 1.5688.

EXAMPLE 14 Preparation of 2-4:hloroethane-thiono-phosphonic acid phenyl ester N-mono-isobutylamide 5 1| o\ Hr -CH P CH NH tie-t H: i fix Yield: 87%. n,,'-: 1.5511. Starting product: compare Example 13.

EXAMPLE 15 Preparation of 2-chloroethane-thiono-phosphonic acid phenyl ester N-mono-phenylamidc Yield: 55%. melting point: 6062C. Starting product: compare Example 13.

EXAMPLE 16 Preparation of 2-chloroethanephosphonic acid phenyl ester N-mono-n-hutylamide 0 H.. 40 c t (H P Analysis; Cl N Calc. for C H ClNO Pz 12.9071: 5.1051; Found: 12.16%; fiji'm The 2-chloroethanephosphonic acid N-mono-nbutylamide chloride used as starting product is pre pared as follows:

73 g (1 mole) nbutylamine are added to 91 g (0.5 mole) 2-chloroethanephosphonic acid dichloride in 1500 ml toluene. Stirring is then effected for 2 hours at 19 room temperature. the salts are filtered off with suc tion. and. after washing with water and drying with sodium sulphate. the solvent is drawn oft. After slight distillation. a colourless oil remains behind. yield: 75 g (6971 of the theory) 2 chloroethanephosphonic acid N-monon-hutylamide chloride. n 1.4962.

EXAMPLE 1? Preparation of 2chloroethane-thiono-phosphonic acid phenyl ester N-mono-n-butylamide NHC H, n

Yield: 70%. n 1.5479. Starting product: 2- chloroethanc-thiono-phosphonic acid N-mono-nbutylamide chloride from 2-chloroethane-thiono phosphonic acid dichloride and n-butylamine. yield: 907r. 2 1.5363.

EXAMPLE 18 Preparation of 2-chloroethane-thiono-phosphonic phenyl ester N-mono-isopropylamide Yield: 3571. mi": 1.5273. Starting product: compare Example 16.

EXAMPLE 2() Preparation of 2-chloroethane-phosphonie acid 4'-hydroxy-phcny1 ester N-mono-n-butylamide NH C 14,. n

Yield: 327r. n 1.5241. Starting product: compare Example 16.

EXAMPLE :1

Prep-.iraton ol' 2chlorocthanethionophosponic acid N-nionoisopropylaniide A solution of 5.5 g ((1.3 mole) of water and 31) g (0.3 mole) triethylamine in 20 ml acetone is added at room temperature to 66 g ((1.3 mole 1 2- chloroethanethionophosphonic acid N- monoisopropylamide chloride in 101) ml benzene. Stirring is then effected for one hour. the precipitated salt is removed and the solvent is drawn off. After slight distillation. a pale oil remains behind. Yield: 54 g (89$? 01 the theory) 2-chloroethanethiophosphonic acid N- monoisopropylamide. n,,'-': l .5419.

Analysis: (I N Calev l'or H flNOPs: 17.65%: (1.95"): Found: 17.43%. 6.49%

Starting product: compare Example 18. Analogously with Example 21. the following compounds are prepared:

EXAMPLE 22 Preparation of Z-chloroethane-thiono-phosphonic acid-N monopheny1amide Yield: 92%. n,,: 1.5662. Starting product: 2- chloroethane-thiono-phosphonic acid N-monophenylamide chloride from 2-chloroethane-thionophosphonic acid dichloride and aniline. yield: 79%. n,,'-": 1.6145.

EXAMPLE 23 Preparation of 2-chloroethane-thiono-phosphonic acid-N-mono-n-buty1amide Yicld:93'/1 mi: 15402. Starting product: ct". Examplc 17.

EXAMPLE 24 Preparation o1 2-chloroethane-phosphonic acid N-mono-n-hutylamide Yield: 61%. n,,': 1.4884. Starting product: compare Example 16.

The above Examples 17 to 23 are carried out in a manner analogous to that of Example 16.

It will he understood that the specification and exam ples are illustrative and are not to be construed as limitative of the invention.

What is claimed is:

1. Method for regulating plant growth which comprises applying to the plant a 2 chloroethanephosphonic acid amido or 2- chloroethanethionophosphonic acid amido compound of the general formula in which X is oxygen or sulfur;

R is lower alkyl of from l to 6 carbon atoms or phenyl; and

R is hydrogen or unsubstituted phenyl or phenyl substituted with nitro. halogen. alkyl or hydroxy; or a salt moiety.

2. Method for regulating plant growth which comprises applying a compound as defined in claim 1 in which R is an alkyl radical with l to 4 carbon atoms or a phenyl radical and R is a hydrogen atom or a phenyl radical which may be substituted by nitro. methyl. hy droxy or chlorine. alone or in admixture with a solid or liquid diluent or carrier.

3. Method as claimed in claim 1 wherein R is phenyl.

4. Method as claimed in claim I wherein said salt moiety is an alkali or alkaline earth metal or ammo mum.

5. Method as claimed in claim 1 wherein said compound is applied in the form of a composition with a solid or liquid carrier. the composition containing from 0.0005 to 27: by weight of said compound.

6. Method as claimed in claim 5 wherein the composition contains from 0.0] to 0.5% by weight of compound.

7. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to promote the growth of plants.

8. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to hinder the growth of plants.

9. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to alter the growth of plants.

10. Method as claimed in claim I wherein said coni pound is applied at the rate ol'0.l to 10kg per hectare.

ll. Method as claimed in claim 10 wherein the rate is l to H) kg per compound per hectare.

12. Method as claimed in claim I wherein said compound is designated as 2-chloroethane-phosphonic acid phenyl ester-N-mono-isopropyl amide.

13. Method as claimed in claim I wherein said compound is designated as Z-chloroethane-phosphonic acid-Z-hydroxy-phenyl ester-N-monoisopropyl amide.

14. Method as claimed in claim I wherein said compound is designated as Z-chloroethane-phosphonic acid-mono-N-isopropyl amide.

15. Method as claimed in claim I wherein said compound is designated as 2-chloroethane-thionophosphonic acid phenyl ester-N-montrmethyl amide.

16. Method for regulating plant growth which com prises applying to a plant seed a 2-chloroethanephosphonic-acid-amido or Z-chloroethaneahionophosphonic acid amido compound. as defined in claim 1.

17. Method for regulating plant growth which comprises applying to a plant habitat a Z-chloroethanephosphonic-acid-amido or 2-chlorocthane-thionophosphonic acid amide compound. as defined in claim 1. 

1. METHOD FOR REGULATING PLANT GROWTH WHICH COMPRISES APPLYING TO THE PLANT A 2-CHLOROETHANEPHOSPHONIC ACID AMIDO OR 2-CHLOROETHANETHIONOPHOSPHONIC ACID AMIDO COMPOUND OF THE GENERAL FORMULA
 2. Method for regulating plant growth which comprises applying a compound as defined in claim 1 in which R is an alkyl radical with 1 to 4 carbon atoms or a phenyl radical and R'' is a hydrogen atom or a phenyl radical which may be substituted by nitro, methyl, hydroxy or chlorine, alone or in admixture with a solid or liquid diluent or carrier.
 3. Method as claimed in claim 1 wherein R'' is phenyl.
 4. Method as claimed in claim 1 wherein said salt moiety is an alkali or alkaline earth metal or ammonium.
 5. Method as claimed in claim 1 wherein said compound is applied in the form of a composition with a solid or liquid carrier, the composition containing from 0.0005 to 2% by weight of said compound.
 6. Method as claimed in claim 5 wherein the composition contains from 0.01 to 0.5% by weight of compound.
 7. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to promote the growth of plants.
 8. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to hinder the growth of plants.
 9. Method as claimed in claim 1 wherein said compound is applied in amounts sufficient to alter the growth of plants.
 10. Method as claimed in claim 1 wherein said compound is applied at the rate of 0.1 to 10 kg per hectare.
 11. Method as claimed in claim 10 wherein the rate is 1 to 10 kg per compound per hectare.
 12. Method as claimed in claim 1 wherein said compound is designated as 2-chloroethane-phosphonic acid phenyl ester-N-mono-isopropyl amide.
 13. Method as claimed in claim 1 wherein said Compound is designated as 2-chloroethane-phosphonic acid-2-hydroxy-phenyl ester-N-mono-isopropyl amide.
 14. Method as claimed in claim 1 wherein said compound is designated as 2-chloroethane-phosphonic acid-mono-N-isopropyl amide.
 15. Method as claimed in claim 1 wherein said compound is designated as 2-chloroethane-thiono-phosphonic acid phenyl ester-N-mono-methyl amide.
 16. Method for regulating plant growth which comprises applying to a plant seed a 2-chloroethane-phosphonic-acid-amido or 2-chloroethane-thiono-phosphonic acid amido compound, as defined in claim
 1. 17. Method for regulating plant growth which comprises applying to a plant habitat a 2-chloroethane-phosphonic-acid-amido or 2-chloroethane-thiono-phosphonic acid amido compound, as defined in claim
 1. 